Document and Entity Information - USD ($)	12 Months Ended
	Mar. 31, 2019	Jun. 26, 2019	Sep. 30, 2018
Document and Entity Information [Abstract]
Entity Registrant Name	PetroGas Co
Entity Central Index Key	0001609258
Document Type	10-K
Document Period End Date	Mar. 31, 2019
Amendment Flag	false
Current Fiscal Year End Date	--03-31
Is Entity's Reporting Status Current?	Yes
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		3,874,473
Entity Public Float			$ 4,544,994
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2020
Entity Emerging Growth Company	true
Entity Small Business	true
Entity Ex Transition Period	false
Entity Well Known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Shell Company	true